Answer this question truthfully
### Question: What causes Hunter syndrome?
### Response: Hunter syndrome is an inherited condition. Boys are most often affected.
The condition is caused by a lack of the enzyme iduronate sulfatase. Without this enzyme, mucopolysaccharides build up in various body tissues, causing damage.
The early-onset, severe form of the disease begins shortly after age 2. A late-onset, mild form causes less severe symptoms to appear later in life.